Snowflakes are ice crystals that form in the sky and fall to the ground. According to the National Oceanic and Atmospheric Administration (NOAA), the arms of a snowflake are formed when “water vapor freezes onto the primary crystal, building new crystals.” Snowflakes are fragile and melt quickly. It was not until people began experimenting with photomicrography that they were able to both preserve and appreciate their beautiful geometry.
Wilson A. Bentley: The Snowflake Man
Wilson A. Bentley (1865-1931) is considered a pioneer in the field of photomicrography. He was a self-educated farmer who admired the beauty of snowflakes so much that he began photographing them.
The official Wilson A. Bentley website briefly describes how he developed a way to photograph snowflakes by “adapting a microscope to a bellows camera.”
Some of his noteworthy accomplishments include being “the first person to photograph a single snow crystal in 1885″ and photographing “more than 5000 snowflakes during his lifetime.”
The website further notes that “his snow crystal photomicrographs were acquired by colleges and universities throughout the world” and that “he published many articles for magazines and journals, including Scientific American and National Geographic.”
Bentley’s lifelong passion for snowflakes is revealed in the following quote that he made toward the end of his life in 1925:
“Under the microscope, I found that snowflakes were miracles of beauty; and it seemed a shame that this beauty should not be seen and appreciated by others. Every crystal was a masterpiece of design and no one design was ever repeated., When a snowflake melted, that design was forever lost. Just that much beauty was gone, without leaving any record behind.”
In 1931, the year that he died, McGraw-Hill published his book called Snow Crystals, which contained more than 2400 snow crystal images.
By Wilson Bentley [Public domain], via Wikimedia Commons
Snow flakes by Wilson Bentley ; http://www.photolib.noaa.gov/htmls/wea02087.htm ; Plate XIX of “Studies among the Snow Crystals … ” by Wilson Bentley, “The Snowflake Man.” From Annual Summary of the “Monthly Weather Review” for 1902. Bentley was a bachelor farmer whose hobby was photographing snow flakes. ; Image ID: wea02087, Historic NWS Collection ; Location: Jericho, Vermont ; Photo Date: 1902 Winter
Modern Snowflake Photomicrography
As time passed, more advanced imaging techniques were developed. Two common methods of photomicrography used today are focus stacking and electron microscopy.
The following snowflake photos are examples of focus stacking images. Wikipedia defines focus stacking as “a digital image processing technique which combines multiple images taken at different focus distances to give a resulting image with a greater depth of field (DOF) than any of the individual source images.”
Source: “Focus Stacking” – Wikipedia
The John Innes Centre, a company that specializes in plant bioimaging, describes the electron microscope as “a type of microscope that uses a beam of electrons to create an image of the specimen.” As a result, it “is capable of much higher magnifications and has a greater resolving power than a light microscope, allowing it to see much smaller objects in finer detail.” Because they are large and expensive, electron microscopes are used primarily by large companies and government organizations. The following snowflake photos were taken by the Agricultural Research Service, the research agency of the United States Department of Agriculture.
Snowflake 300um LTSEM, 13368.jpg
By user:Brian0918 (Credit: Erbe, Pooley: USDA, ARS, EMU) [Public domain], via Wikimedia Commons
Snow crystals 2b.jpg
This image is a JPEG version of the original PNG image at File:Snow_crystals_2b.png.
Photo credits from original PNG image:
By Electron and Confocal Microscopy Laboratory, Agricultural Research Service, U. S. Department of Agriculture  (http://emu.arsusda.gov/snowsite/) [Public domain], via Wikimedia Commons
See page for author [Public domain], via Wikimedia Commons